Cervical region

Cervical spine due to its position, complex structure and great mobility is vulnerable to injuries. It is a complex and vital region. Vital knowledge of cervical region is essential for physician, while dealing with the patients having the problems of cervical region.

Components of the structure of cervical spine:

1.      Bony Structure

The cervical spine is composed of first seven vertebrae of the vertebral column. The seven cervical vertebrae are the smallest movable vertebrae and identifiable by their transverse processes, which are perforated by a foramen

a.       Typical cervical vertebrae- 2nd to 6th cervical vertebrae:

b.      The atlas – first cervical vertebra (C1)

c.       The axis – Second Cervical Vertebra (C2)

d.      The seventh Cervical Vertebra (C7)

e.        

2.      Musculature

The muscles of the neck are grouped according to their position. These groups are

as follows

a. Superficial and Lateral cervical muscles

b. Anterior Vertebral muscles

c. Lateral Vertebral muscles

d. Deep muscles of the back of the neck

e. Sub – occipital muscles

3. Articulations

(A) Intervertebral articulations – It is divided into two parts.

a. Articulations of vertebral bodies

b. Articulations of vertebral arches.

(B) Articulation of vertebral column with cranium:

The articulation of vertebral column with cranium involves the paired atlanto-occipital joints and ligaments connecting the axis and occipital bone.

4. Neural and Vascular contents.

Cervical Spondylosis

Definition:

Cervical spondylosis is a degenerative condition of the cervical spine. There is degeneration of inter-vertebral disc, with its protrusion and bony overgrowth of adjacent vertebrae causing compression of roots, cord or both. Occasionally it is associated with non-compressive myelopathy consequent to vascular degeneration.

Pathogenesis:

This is compound effect of the following processes:

a. The initial change is a decrease in the water content of the nucleus pulposus, the

central portion of the disc. As the disc dehydrates, it decreases in height and has

less ability to resist loading and stress,

Disc degeneration leading to its thinning and protrusion of the nucleus

pulposus posteriorly or herniation through fear in the fibrous annuloses laterally;

posterior herniation tends to produce compression of the spinal cord and lateral

bulging produces compression of roots.

b. Osteophytic spur formation on the posterior aspect of the vertebral body leading

to the ‘spondylotic bar’, which is the core pathology resulting in a horizontal

compression of the anterior aspect of the cord. Osteophytic extension of the bar,

laterally associated with articulatory hypertrophic changes or encroachment of the

intervertebral neural foramina by osteophytes developing from the rim of the

foramina, often cause additional entrapment radiculopathy. Anterior ostephytic

spur formation is usually symptom less but occasionally produces dysphagia.

c. Partical sublaxation of vertebrae causing impinging of osteophytes on the nerve

roots during movement of the neck.

d. Hypertrophy of the dorsal spinal ligament and dorsilateral facet articulation or

bucking of the dorsal spinal ligament particularly during extension of the neck.

All these may cause further narrowing of the sagittal diameter of a spinal canal,

which might have been congenitally narrow.

e. Encroachment of the vertebral foramina where the vertebral artery is lodged

producing compromise of the arterial lumen and significant vetebro – basilar

ischaemia, leading to brainstem signs like vertigo, tinnitus, intermittent blurring

of vision and occasionally episodes of retroocular pain. This apart, the

architectural pattern of the vasculature of the cervical cord may further affect the

cord lesion significantly.

f. Presence of congenital spinal canal stenosis; although the radiographic findings of

spondylosis are fairly common in the elderly, patients develop myelopathy or

radiculopathy only if spondylotic changes are associated with congenitally narrow

canal or foramina. If the shortest AP diameter is 13mm or greater, it is unlikely

that spondylotic changes are the cause of cord compression.

CLINICAL FEATURES:

The symptoms are related to

(a) Spinal symptoms – Neckpain, medial scapular pain and shoulder pain probably

originate in the disc and spine.

(b) Root compression (Radiculopahty) – The range of movement is reduced

particularly during rotation and lateral movement of the head. Pain starts from the

trapezius ridge (C4), tips of the shoulder (C5), anterior part of the arm (C6), radial

forearm (C6), and often the thumb (C8) or all the fingers (C6, C7, C8).

The pain worsens with movement of the neck, coughing or sneezing or straining.

The clinical signs are motor weakness and wasting of proximal muscles or small

muscles of the hand depending on the roots compressed. In addition, there is also

areflexia and redicular sensory impairment. Sometimes L’hermitt’s sign or

‘barber’s chair sign’ can be elicited; this consists of tingling in all four limbs or

electric shock – like feelings down the back on flexing the neck. The roots most

often affected are, in order, C6, C7, and C5, C6, C8 and D1 are infrequently

affected. Occasionally, the shoulderhand syndrome or the so – called frozen

shoulder ensues if symptoms are unattended for some time.

(c) Compressive cervical myelopathy – This condition occurs less frequently than

root syndromes. There is some evidence that the patient has to be predisposed to

compression by a congenitally narrow canal (Cervical canal stenosis) and usually

presents with a progressive spastic paraparesis; later, bladder and bowel

involvement is added to sensory inpairment with a level.

(d) Combined root and cord compression – In a few cases, clinical features of both

radiculopathy and myelopathy are combined. In such a combined lesion occurring

at C5 level, the C5 root is compressed by lateral protrusion and the cord below

this level is compressed by medial lesion. The reflexes are asymmetrical, with

classically abscent or decreased supinator and exaggerated triceps jerks;

occasionally an inverted supinator jerk is elecited when on testing for supinator

response, there is finger flexion in the absence of the normal supinator response,

indicating a lesion of C5 with myelopathy below.

(e) Vascular insufficiency – Some times a completely different category of symptoms

may occur, viz. evidence of vertebro basilar insufficiency, this may be due to

permanent narrowing or kinking of the vertebral artery due to inter-vertebral

foraminal encroachment by ingrowing osteophytes from the bony wall of the

vertebral canal; it may produce intermittent or perpetual vertigo. Neck movement

may initiate or exacerbate vertigo by temporary compression of the vertebral

artery leading to further insufficiency.

The other symptoms like tinnitus, visual blurring, etc. have already been

referred too. As discussed earlier, there may be a non compressive myelopathy

due to compromised vasculature. In such cases, pain is usually absent and

myelography fails to reveal any spinal block; this is sometimes referred to as

cervical myelopathy (or cervical spondylotic myelopathy).

Nystagmus, though rare, is sometimes seen and is probably due to

involvement of the posterior longitudinal bundle in a high cervical lesion.

INVESTIGATION:

A plain X-ray of the cervical spine is helpful. There is impairment of natural

cervical lordosis, reduction of intervertebral spaces, osteophytic projection leading to

distortion and encroachment of intervertebral foramina (in appropriate obligue view), and

shortening of AP diameter of the cervical canal in few cases.

For demonstration of compressive myelopathy, a contrast myelogram is

necessary. It shows the presence of multiple disc protrusions as a negative indentation of

the contrast column or total extradural obstruction. CT scan with or without contrast is

preferred if available. MRI is another useful mode of invetigation.

Ayurvedic texts, there are many other ailments, which are related to neck and

demonstrate the similar symptoms. So it is worthy to have a look on these manifestations.

This will help in differential doagnosis and also in justification to the paralance with

Griva Hundanam.

Those diseases are:

1. Manya Stambha

2. Manya Graha

3. Griva Stambha

4. Asthi Majja Gatavata

5. Sandhigata Vata

6. Visvaci

7. Sirograha

Manya Stambha: As noted earlier in the description of Manya Stambha, its aetiopathogenesis

has been dealt in almost all the texts. Manya – Stambha, entity cannot be

considered as cervical spondylosis because of its acute onset, and having no mention of

pain and is described along with Antarayama and Bahirayama. It is also considered as

main symptom of Apatanaka. In addition, at the last in this condition Jatru Vakrata

happens. Whereas in cervical spondylosis is a slow process with pain and restriction of

the movements are the main symptoms. Moreover, the Manya Stambha occurs due to the

involvement of muscles whereas in cervical spondylosis, actual pathology lies in the

cervical intervertebral discs. So, it cannot be correlated with cervical spondylosis.

Manyagraha & Griva Stambha: These two disorders have been described as symptoms

of other disease as well as separate entities. The meaning itself suggest that the stiffness

of Griva muscles may cause this entity whereas in cervical spondylosis other symptoms

are also accompanied.

Siro or Sira Graha has also the different aetio-pathogenesis. In which severe headache

may be found. But due to absence of other symptoms, it cannot be considered as cervical

spondylosis.

Asthimajjagata Vata: The symptoms of Asthimajjagata Vata explained in the texts can

be found in this condition and these symptoms are similar to some extent in comparison

to cervical spondylosis. But, no justification can be given to the neurological symptoms

exhibited. Even though these symptoms can be taken in to consideration up to the stage;

when nerve root are not compressed. It can be considered as the later stage of

Asthimajjagata Vata.